Spark-gap.



I. S. HIRSUH.

SPARK GAP.

APPLICATION FILED JULY 18,1907.

Patented Sept. 15, 1908.

ZSHEETS-SHEBT 1.

I. S. HIRSGH.

SPARK GAP.

APPLICATION FILED JULY 18,1907.

898,888, Patented Sept. 15, 1908.

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UNITED STATES PATENT oFFIoE;

ISAAC s. HIRSOH, OF'NEW YORK, N. Y., ASSIGNOR'TO E. B. MEYROWITLOF NEWYoRK, N. Y;

SPARK-GAP.

Specification of Letters Patent. Application filed July 18, 1907. SerialNo. 384,370.

Patented Sept. 15, 1908..

To all whom it may concern:

Be it known that I, ISAAC S. Hmscn, a citizen of the United States,residing in the city of New York, county and State of New York, haveinvented certain new and useful to provide a spark-gap betweeneach'connection of the secondary winding of the'induction coil and thevacuum tube in order to secure the necessary resistance to the currentto obtain the desired results. Heretofore it has been necessary to turnoil the current in the primary coil when it has been desired to changethe resistance in the secondary circuit. By the use of my improvedapparatus the resistance may be re ulated as desired While-theapparatus-is in ull operation thus securing perfect results in theminimum time.

Another feature of my invention is the mounting of the disks with thecentral projectingpoints in a revoluble frameso that the resistance canbe-regulated to suit the work in hand by compelling the current to passfrom disk to point or from point to disk as desired, the latter ofieringthe least resistance.

My apparatus further consists in slidably mounting one member of the gapin a frame to which is secured the other member andprovidin operatingmechanism so constructed that t e gap connected with either pole of thesecondary winding of the induction coil may be operated so as toregulate the resistance to secure the best results, its principaladvantage being in the fact that as the resistance can be regulatedwhile the discharge is passing into the vacuum tube the resistance maybe increased as the vacuum falls.

The construction and operation of In imroved spark gap will bedescribedin etail hereinafter, and illustrated in the accompanyingdrawings, in which Figure 1 is a view of a simple formof X- rayapparatus with my improved s ark-gap A indicates the cabinet containingthe induction coil used in X-ray apparatus, B the wires leading to theprimary coil thereof, and C the binding posts connected with thesecondary coil.

D indicates the X-ray tube.

' In all apparatuses of thisnature it is necessary to provide aspark-gap between the binding posts 0 and the tube D in order toregulate the resistance to the current from the secondary coil and myinvention consists in the construction of the spark ga s which aremounted on bases 1 secured ad acent to cabinet A. Each of the bases 1 isprovided with a grooved slideway 2 in which is slidably mounted a bar 3having a rack bar 4 secured to its under-side.

' 5 indicates a sleeve j ournaled in each base 1 having an annular gearface 6 thereon that meshes with the rack bar 4, said sleeves 5 beingrovided with notches 7 in one end thereo 8 indicates a rod slidably andrevolubly mounted in sleeves 5 and having pins 9 projecting laterallytherefrom to engage notches 7 to rotate the sleeves. The bases 1 andbars 2 are constructed of a poor conductor of electricity such as wood.

10 indicates a metal plate secured to each bar 3 having a binding post11 mounted thereon to receive one of the wires 12 connected with one ofthe binding posts C, and an L-shaped conductor rod 13 secured theretowith its free end extending lengthwise of the bar 3.

Mounted on the top of each base 1 is a circular plate 14 of anon-conducting material such as vulcanized fiber, or othernon-conductor. v

15 indicates a bar made of vulcanized fiber, or other non-conductingmaterial revolubly mounted on plate 14 and having end posts 16 made ofmetal secured to said frame. The end posts 16 are provided with holes 17to receive the free end of conductor rod 13.

18 indicates disks having points 18 projecting centrally from one sidethereof and mounted on supports 19 of non-conducting material secured toposts 16, said su ports may consist of rods 20 of vulcanized her orother non-conductor surrounded by glass tubes 21, as shown, or any othernon-conducting material may be substituted therei 2 rings interposedbetween the end disks and posts 16. 1 v or projection on the;

' contact post 28 to which is secured a wire 29 connected with one orthe other poles of the X-ray tube D.

30 indicatesa screw rod mounted on the rod and having a head 31; toengage the free end of L-shaped conductor rod 13 when the bar 3 is itsinnermost osition. I

As shownin the drawings t e ends of conductor rods 13 engage the heads31 of the screw rods so t at there is a free circuit between theinduction coil and the X-ray tube. Should it be necessary, however, toput a resistance in the circuit the bars 3 in the bases 1- are moved outby .turning the sleeves 6 in said bases by means of rod 8 and pins 9that engage notches 7 in the ends of said sleeves, so that the ends ofconductor rods 13 are at a distance from the heads 31 of screw rods30-and the current is compelled to pass from said rods 13 to the disks18 and jump from disk to disk to the end posts 16-so as to com lete thecircuit. By this construction it 1 be understood that the resistance inthe circuit may be increased or diminished as desired for the mostefficient operation of the X-ra tube and thatjsuch regulation may be eected while the. tube is l ghted. It will also be understood that bymanipulating the frames 15 so that the points 18 on the disks '18 pointin the direction of the negative, '5, e. so that the current passes fromone point to the adj acentdisk, a free circuit with very low resistanceis allowed, while when the points are in the opposite direction ortowards the negative, so thatithe current passes from the fiat side ofthe disks to the oints the current is retarded or held him Having thusdescribed my invention what I claim is Y i Y 1. In a spark gap, onemember thereof consisting of a revoluble frame, and non-ro- -tatahle,conducting disks secured to said frame, substantially as shown anddescribed. 2. In a s ark gap, one member thereof consisting o arevoluble frame including two uprights, and disks securedbetween saiduprights, substantially as shown and described.

3. In a spark gap, a stationary base, a horizontal bar of non conductingmaterial revolubly secured thereto, upright posts of metal secured tothe ends of said horizontal bar, rods of non-conducting material confnecting said posts, and a series of disks end- . ceases v 4. A smark-gapoperating mechanism for X ra -machines, comprising stationary bases, arsslidably mounted on said bases, the two members of each gap secured tothe bases and bars respective y and means to actuate saidbars,substantiallyas shown and her of the gap comprising a series ofdisks havin central oints ro'ectin from one side thereof, said diskssecured to a frame' revolubly mounted on the base, substantially asshown and described.-

6. A spark-ggp operating mechanism for X ray mac 'nes comprisingstationary bases, a bar slidably mounted on each base, one of the twomembers of each gap secured to the base and the other to the barslidably mounted thereon, a rack bar secured to the bottom of eachslidable bar, a gear pinion journaled in each base and meshing with eachrack-bar, and means to rotate said inions, substantially as shown anddescri ed.

7. A spark-gap operating mechanism for X ray machines comprisingstationary bases, a bar slidably mounted on each base, one of the twomembers of each gap secured to the base and the other to the barslidably mounted thereon, a rack bar secured to the bottom ofeachslidable bar, a sleeve journaled in each base and having a notched end,an annular gear face on each sleeve to mesh with the rack-bar aforesaid,a rod slidably and revolubly mounted in said sleeves, and pinsprojecting from said rod to enga e the notches in the ends of thesleeves, su stantially as shown and described.

8. A spark-gap operating mechanism for X ray bases, a bar slidablymounted on each base, a rack-bar secured to the bottom of each bar, agear pinion j ournaled in each base and meshing with therack-bars'aforesaid, means machines comprising stationary to rotate saidpinions, one member of the spark gap secured to the slidable bar, the

notches in one of their ends, an annular gear face on each sleeve tomesh with the rack-bar aforesaid, a rod slidably and revolubly mountedin said sleeves, pins projecting from said rod to engage the notches onthe ends of the sleeves, one member of the gap secured to the slidablebar, the other member of the gap comprising a series of disks havingcentral points projecting from one side thereof, said disks secured to aframe revolubly mounted on the base, substantially as shown anddescribed.

10. A spark-gap operating mechanism for X ray mac es comprisingstationary bases, a bar slidably mounted on each base, a rack bar on thebottom of each slidable bar, a sleeve journaled in each base havingnotches in one of its ends and a gear face intermediate of its ends toengage said rack bar, a rod slidably and revolubly mounted in saidsleeves and having laterally projecting pins to engage the notches inthe ends of the sleeves, a metal plate secured to each bar, a

binding post secured to each plate, an L- shaped rod secured to theplate, a frame revolubly mounted on the base, a series of disks mountedon said frame, the frame and disks being perforated to receive said L-shaped rod, and a conductor secured to the base and in contact with theframe to conduct the current to or from the gap, substantially as shownand described.

In testimony whereof I hereto affix my signature in the presence of twowitnesses.

ISAAC S. HIRSOH.

Witnesses:

L. BURNS, Jr., M. S. OLAwsoN.

